Heterocyclic compound and organic light-emitting diode including the same

ABSTRACT

A heterocyclic compound represented by Formula 1 and an organic light-emitting diode including the same:

CROSS-REFERENCE TO RELATED APPLICATION

Korean Patent Application No. 10-2013-0096893, filed on Aug. 14, 2013, in the Korean Intellectual Property Office, and entitled: “Heterocyclic Compound and Organic Light-Emitting Diode Including The Same,” is incorporated by reference herein in its entirety.

BACKGROUND

1. Field

One or more embodiments relate to a heterocyclic compound and an organic light-emitting diode including the same.

2. Description of the Related Art

Organic light-emitting diodes (OLEDs), which are self-emitting diodes, may have wide viewing angle, excellent contrast, quick response, high brightness, excellent driving voltage characteristics, and can provide multicolored images.

SUMMARY

Embodiments may be realized by providing a heterocyclic compound represented by Formula 1:

wherein:

R₁ is a substituted or unsubstituted C₁-C₆₀ alkyl group, a substituted or unsubstituted C₃-C₆₀ cycloalkyl group, a substituted or unsubstituted C₆-C₆₀ aryl group, a substituted or unsubstituted C₂-C₆₀ heteroaryl group, or a substituted or unsubstituted C₆-C₆₀ condensed polycyclic group,

Ar₁ to Ar₄ are each independently a substituted or unsubstituted C₆-C₆₀ aryl group, a substituted or unsubstituted C₂-C₆₀ heteroaryl group, or a substituted or unsubstituted C₆-C₆₀ condensed polycyclic group, and

X, Y, and Z are each independently a single bond, a substituted or unsubstituted C₆-C₆₀ arylene group, a substituted or unsubstituted C₂-C₆₀ heteroarylene group, or a substituted or unsubstituted C₆-C₆₀ condensed polycyclic group.

According to one or more embodiment, an organic light-emitting diode includes a first electrode; a second electrode facing the first electrode; and an organic layer disposed between the first electrode and the second electrode, the organic layer including the above-described heterocyclic compound.

According to one or more embodiments, an organic light-emitting diode includes a first electrode that is electrically connected to a source electrode or a drain electrode in a thin film transistor (TFT).

BRIEF DESCRIPTION OF THE DRAWING

Features will become apparent to those of skill in the art by describing in detail exemplary embodiments with reference to the attached drawings in which:

FIG. 1 illustrates a schematic view of a structure of an organic light-emitting diode (OLED) according to an embodiment.

DETAILED DESCRIPTION

Example embodiments will now be described more fully hereinafter with reference to the accompanying drawings; however, they may be embodied in different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey exemplary implementations to those skilled in the art.

In the drawing figures, the dimensions of layers and regions may be exaggerated for clarity of illustration. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. Expressions such as “at least one of,” when preceding a list of elements, modify the entire list of elements and do not modify the individual elements of the list.

According to an embodiment, there is provided an organic light-emitting diode (OLED) including a compound represented by Formula 1 below:

In formula 1 above,

R₁ may be a substituted or unsubstituted C₁-C₆₀ alkyl group, a substituted or unsubstituted C₃-C₆₀ cycloalkyl group, a substituted or unsubstituted C₆-C₆₀ aryl group, a substituted or unsubstituted C₂-C₆₀ heteroaryl group, or a substituted or unsubstituted C₆-C₆₀ condensed polycyclic group,

Ar₁ to Ar₄ may each independently by a substituted or unsubstituted C₆-C₆₀ aryl group, a substituted or unsubstituted C₂-C₆₀ heteroaryl group, or a substituted or unsubstituted C₆-C₆₀ condensed polycyclic group,

X, Y, and Z may each independently be a single bond, a substituted or unsubstituted C₆-C₆₀ arylene group, a substituted or unsubstituted C₂-C₆₀ heteroarylene group, or a divalent linking group such as a substituted or unsubstituted C₆-C₆₀ condensed polycyclic group.

Substituents of the compound represented by Formula 1 used herein will now be described in detail.

According to an embodiment, R₁ in Formula 1 may be represented by one of Formulae 2a to 2d below:

In Formulae 2a to 2d,

Q₁ may be —CR₁₁R₁₂—;

R₁₁, R₁₂, and Z₁ may each independently be a hydrogen atom, a deuterium atom, a substituted or unsubstituted C₁-C₂₀ alkyl group, a substituted or unsubstituted C₆-C₂₀ aryl group, a substituted or unsubstituted C₂-C₂₀ heteroaryl group, a substituted or unsubstituted C₆-C₂₀ condensed polycyclic group, a halogen group, a cyano group, a nitro group, a hydroxyl group, or a carboxyl group, wherein Z₁ is identical to or different from each other when there is a plurality of Z₁s;

p is an integer of 1 to 7; and

* indicates a binding site.

According to another embodiment, Ar₁ to Ar₄ in Formula 1 may each independently be represented by one of Formulae 3a to 3f below:

In Formulae 3a to 3f,

Q₁ may be —CR₁₁R₁₂—;

R₁₁, R₁₂, and Z₁ may each independently be a hydrogen atom, a deuterium atom, a substituted or unsubstituted C₁-C₂₀ alkyl group, a substituted or unsubstituted C₆-C₂₀ aryl group, a substituted or unsubstituted C₂-C₂₀ heteroaryl group, a substituted or unsubstituted C₆-C₂₀ condensed polycyclic group, a halogen group, a cyano group, a nitro group, a hydroxyl group, a carboxyl group, or a substituted or unsubstituted C₃-C₂₀ alkylsilyl group, wherein Z₁ is identical to or different from each other when there is a plurality of Z₁s;

p is an integer of 1 to 9; and * indicates a binding site.

According to another embodiment, X, Y, and Z in Formula 1 may each independently be a single bond or represented by one of Formulae 4a to 4e below:

In Formula 4a to 4e,

Q₁ may be —CR₁₁R₁₂—;

R₁₁ and R₁₂ may each independently be a hydrogen atom, a deuterium atom, a substituted or unsubstituted C₁-C₂₀ alkyl group, a substituted or unsubstituted C₆-C₂₀ aryl group, a substituted or unsubstituted C₂-C₂₀ heteroaryl group, a substituted or unsubstituted C₆-C₂₀ condensed polycyclic group, a halogen group, a cyano group, a nitro group, a hydroxyl group, or a carboxyl group; and

* indicates a binding site.

According to another embodiment, R₁ in Formula 1 may be represented by one of Formulae 5a and 5b below:

In Formulae 5a and 5b, * indicates a binding site.

According to another embodiment, Ar₁ to Ar₄ in Formula 1 may each independently be represented by one of Formulae 6a to 6d below:

In Formulae 6a to 6d, * indicates a binding site.

According to another embodiment, X, Y, and Z in Formula 1 may each independently be a single bond or represented by one of Formulae 7a and 7b below:

In Formulae 7a and 7b, * indicates a binding site.

Hereinafter, definition of representative substituents used herein will now be described in detail (In this regard, numbers of carbons limiting a substituent are non-limited, and thus the substituent characteristics are not limited. Substituents not used herein are defined according to the general definition).

The unsubstituted C₁-C₆₀ alkyl group used herein may be linear or branched. Non-limiting examples of the unsubstituted C₁-C₆₀ alkyl group are a methyl group, an ethyl group, a propyl group, an iso-butyl group, a sec-butyl group, a pentyl group, an iso-amyl group, hexyl group, a heptyl group, an octyl group, a nonanyl group, and a dodecyl group. At least one hydrogen atom of the unsubstituted C₁-C₆₀ alkyl group may be substituted with a deuterium atom, a halogen group, a hydroxyl group, a nitro group, a cyano group, an amino group, an aminido group, a hydrazine, a hydrzone, a carboxyl group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group of a salt thereof, a C₁-C₁₀ alkyl group, a C₁-C₁₀ alkoxy group, a C₂-C₁₀ alkenyl group, a C₂-C₁₀ alkynyl group, a C₆-C₁₆ aryl group, or a C₂-C₁₆ heteroaryl group.

The unsubstituted C₂-C₆₀ alkenyl group indicates an unsubstituted alkyl group having at lest one carbon-carbon double bond in the center or at a terminal thereof. Examples of the unsubstituted C₂-C₆₀ alkenyl are an ethenyl group, a propenyl group, and a butenyl group. At least one hydrogen atom of the unsubstituted C₂-C₆₀ alkenyl group may be substituted with the same substituent as used in the substituted alkyl group described above.

The unsubstituted C₂-C₆₀ alkynyl group indicates an unsubstituted alkyl group having at least one carbon-carbon triple bond in the center or at a terminal of thereof. Examples of the unsubstituted C₂-C₆₀ alkynyl group are acetylene, propylene, phenylacetylene, naphthylacetylene, isopropylacetylene, t-butylacetylene, and diphenylacetylene. At least one hydrogen atom of the unsubstituted C₂-C₆₀ alkynyl group may be substituted with the same substituent as used in the substituted alkyl group described above.

The unsubstituted C₃-C₆₀ cycloalkyl group indicates an alkyl group in the form of C₃-C₆₀ rings, and at least one hydrogen atom of the unsubstituted C₃-C₆₀ cycloalkyl group may be substituted with the same substituent as used in the C₁-C₆₀ alkyl group described above.

The unsubstituted C₁-C₆₀ alkoxy group has a structure of —OA (wherein, A is an unsubstituted C₁-C₆₀ alkyl group as described above). Non-limiting examples of the unsubstituted C₁-C₆₀ alkoxy group are a methoxy group, and ethoxy group, a propoxy group, an isopropyloxy group, a butoxy group, and a pentoxy group. At least one hydrogen atom of the unsubstituted C₁-C₆₀ alkoxy group may be substituted with the same substituent as used in the substituted alkyl group described above.

The unsubstituted C₆-C₆₀ aryl group indicates a carbocyclic aromatic system including at least one ring. When the unsubstituted C₆-C₆₀ aryl group has two or more of rings, the rings may be fused or linked to each other by a single bond. The term ‘aryl’ refers to an aromatic system, such as phenyl, napthyl, and anthracenyl. Also, at least one hydrogen atom of the unsubstituted C₆-C₆₀ aryl group may be substituted with the same substituent as used in the C₁-C₆₀ alkyl group described above.

Examples of the substituted or unsubstituted C₆-C₆₀ aryl group are a phenyl group, a C₁-C₁₀ alkylphenyl group (e.g., an ethylphenyl group), a biphenyl group, a C₁-C₁₀ alkylbiphenyl group, a C₁-C₁₀ alkoxybiphenyl group, an o-, m-, and p-toryl group, an o-, m-, and p-cumenyl group, a mesityl group, a phenoxyphenyl group, an (α,α-dimethylbenzene)phenyl group, an (N,N′-dimethyl)aminophenyl group, an (N,N′-diphenyl)aminophenyl group, a pentalenyl group, an indentyl group, a naphtyl group, a C₁-C₁₀ alkylnaphtyl group (e.g., a methylnaphtyl group), a C₁-C₁₀ alkoxynaphtyl group (e.g., a methoxynaphtyl group), an anthracenyl group, an azulenyl group, a heptalenyl group, an acenaphtylenyl group, a phenalenyl group, a fluorenyl group, an anthraquinolyl group, a methylanthryl group, a phenanthryl group, a tripenylene group, a pyrenyl group, a chrycenyl group, an ethyl-chrysenyl group, a picenyl group, a perylenyl group, a pentaphenyl group, a pentacenyl group, a tetraphenylenyl group, a hexaphenyl group, a hexacenyl group, a rubicenyl group, a coroneryl group, a trinaphtylenyl group, a heptaphenyl group, a heptacenyl group, a pyranthrenyl group, and an ovalenyl group.

The unsubstituted C₂-C₆₀ heteroaryl group used herein may include one, two, three, or four hetero atoms selected from N, O, P, or S. When the unsubstituted C₂-C₆₀ heteroaryl group has two or more of rings, the rings may be fused or linked to each other by a single bond. Examples of the unsubstituted C₂-C₆₀ heteroaryl group are a pyrazolyl group, an imidazolyl group, an oxazolyl group, a thiazolyl group, a tirazolyl group, a tetrazolyl group, an oxadiazolyl group, a pyridinyl group, a pyridazinyl group, a pyrimidinyl group, a triazinyl group, a carbzol group, an indolyl group, a quinolinyl group, an isoquinolinyl group, and a dibenzothiophene group. In addition, at least one hydrogen atom of the unsubstituted C₂-C₆₀ heteroaryl group may be substituted with the same substituent as used in the unsubstituted C₁-C₆₀ alkyl group described above.

The unsubstituted C₆-C₆₀ aryloxy group is a group represented by —OA₁, wherein A₁ is a C₆-C₆₀ aryl group. An example of the unsubstituted C₆-C₆₀ aryloxy group is a phenoxy group. At least one hydrogen atom of the unsubstituted C₆-C₆₀ aryloxy group may be substituted with the same substituent as use din the unsubstituted C₁-C₆₀ alkyl group described above.

The unsubstituted C₆-C₆₀ arylthio group is a group represented by —SA₁, wherein A₁ is a C₆-C₆₀ aryl group. Examples of the unsubstituted C₆-C₆₀ arylthio group are a benzenethio group and a naphtylthio group. At least one hydrogen atom of the unsubstituted C₆-C₆₀ arylthio group may be substituted with the same substituent as used in the unsubstituted C₁-C₆₀ alkyl group described above.

The unsubstituted C₆-C₆₀ condensed polycyclic group used herein refers to a substituent including at lest two rings, wherein at least one aromatic ring and/or at least one non-aromatic ring are fused to each other, or refers to a substituent having an unsaturated group in a ring that may not form a conjugated structure. Thus, the unsubstituted C₆-C₆₀ condensed polycyclic group is distinct from an aryl group or a heteroaryl group in terms of being non-aromatic.

According to another embodiment, examples of the compound represented by Formula 1 include compounds 2, 12, 24, 32, 41, 50, and 63:

According to another embodiment, an organic-light emitting diode (OLED) includes a first electrode; a second electrode; and an organic layer that is disposed between the first electrode and the second electrode, the organic layer including the heterocyclic compound represented by Formula 1.

The organic layer may include at least one layer selected from a hole injection layer (HIL), a hole transport layer (HTL), a functional layer having both hole injection and hole transport capabilities (hereinafter, referred to as a “H-functional layer”), a buffer layer, an electron blocking layer (EBL), an emission layer (EML), a hole blocking layer (HBL), an electron transport layer (ETL), an electron injection layer (EIL), and a functional layer having both electron injection and electron transport capabilities (hereinafter, referred to as an “E-functional layer”).

In greater detail, the organic layer may be an EML, for example a blue EML.

According to another embodiment, the organic layer may include an EIL, an ETL, an E-functional layer having both electron injection and electron transport capabilities, an EML, and HIL, an HTL, or an H-functional layer having both hole injection and hole transport capabilities, wherein the EML may further include an anthracene-based compound, an arylamine-based compound, or a styryl-based compound.

According to another embodiment, the organic layer may include an EIL, an ETL, an E-functional layer having both electron injection and electron transport capabilities, and EML, and HIL, an HTL, or an H-functional layer having both hole injection and hole transport capabilities, wherein at least one layer of a red EML, a green EML, a blue EML, and a white EML of the EML may include a phosphorescent compound. The HIL, the HTL, or the H-functional layer having both hole injection and hole transport capabilities may include a charge-generating material. The charge-generating material may be a p-dopant, and the p-dopant may be a quinone derivative, a metal oxide, or a cyano group-containing compound.

According to another embodiment, the organic layer may include an ETL, and the ETL may include an electron-transporting organic compound and a metal complex. Here, the metal complex may be a lithium (Li) complex.

The term “organic layer” used herein refers to a single layer and/or a multi-layer disposed between the first electrode and the second electrode of the OLED.

FIG. 1 illustrates a schematic view of a structure of the OLED according to an embodiment. Hereinafter, a structure and a manufacturing method of the OLED according to an embodiment will be described in detail with reference to FIG. 1.

A substrate (not illustrated) may be any substrate that can be in used in an OLED. For example the substrate may be a glass substrate or a transparent plastic substrate with excellent mechanical strength, thermal stability, transparency, surface smoothness, ease of handling, and water resistance.

The first electrode may be formed by depositing or sputtering a first electrode-forming material on the substrate. When the first electrode is an anode, a material having a high work function may be used as the first electrode-forming material to facilitate hole injection. The first electrode may be a reflective electrode or a transmission electrode. Examples of the first electrode-forming material include indium tin oxide (ITO), indium zinc oxide (IZO), tin oxide (SnO₂), and zinc oxide (ZnO). When magnesium (Mg), aluminum (Al), aluminum-lithium (Al—Li), calcium (Ca), magnesium-indium (Mg—In), or magnesium-silver (Mg—Ag) are used, the first electrode may be formed as a reflective electrode.

The first electrode may have a single-layer structure or a multi-layer structure including at least two layers. For example, the first electrode may have a three-layered structure of ITO/Ag/ITO.

The organic layer may be disposed on the first electrode.

The organic layer may include an HIL, and HTL, a buffer layer (not illustrated), an EML, an ETL, or an EIL.

An HIL may be formed on the first electrode by various methods, such as vacuum deposition, spin coating casting, and Langmuir-Blodgett (LB) deposition.

When the HIL is formed by vacuum deposition, the vacuum deposition conditions may vary according to the compound that is used to form the HIL, and the desired structure and thermal properties of the HIL to be formed. For example, the vacuum deposition may be performed at a temperature in a range of about 100° C. to about 500° C., a pressure in a range of about 10⁻⁸ torr to about 10⁻³ torr, and a deposition rate in a range of about 0.01 Å/sec to about 100 Å/sec.

When the HIL is formed by spin coating, the coating conditions may vary according to the compound that is used to form the HIL, and the desired structure and thermal properties of the HIL to be formed. For example, the coating rate may be in a range of about 2,000 to about 5,000 rpm, and a temperature at which heat treatment is performed to remove a solvent after coating may be in a range of about 80° C. to about 200° C.

Exemplary HIL materials include N,N′-diphenyl-N,N′-bis-[4-(phenyl-m-tolyl-amino)-phenyl]-biphenyl-4,4′-diamine, (DNTPD), a phthalocyanine compound such as copper phthalocyanine, 4,4′,4″-tris (3-methylphenylphenylamino) triphenylamine (m-MTDATA), N,N′-di(1-naphthyl)-N,N′-diphenylbenzidine (NPB), TDATA, 2-TNATA, polyaniline/dodecylbenzenesulfonic acid (Pani/DBSA), poly(3,4-ethylenedioxythiophene)/poly(4-styrenesulfonate) (PEDOT/PSS), polyaniline/camphor sulfonicacid (Pani/CSA), and polyaniline/poly(4-styrenesulfonate) (PANI/PSS):

A thickness of the HIL may be in a range of about 100 Å to about 10,000 Å, for example, about 100 Å to about 1,000 Å. Maintaining the thickness of the HIL within the above ranges may help provide the HIL with satisfactory hole injecting capabilities without a substantial increase in a driving voltage.

Then, an HTL may be formed on the HIL by various methods, such as vacuum deposition, spin coating, casting, and LB deposition. When the HTL is formed by vacuum deposition or spin coating, the deposition and coating conditions may be similar to those for the formation of the HIL, although the deposition and coating conditions may vary according to the compound that is used to form the HTL.

Exemplary HTL materials include a carbazole derivative such as N-phenylcarbzole and polyvinylcarbzole, N,N′-bis(3-methylphenyl)-N,N′-diphenyl-[1,1-biphenyl]-4,4′-diamine (TPD), 4,4′,4″-tris(N-carbazolyl)triphenylamine) (TCTA), and N,N′-di(1-naphthyl)-N,N′-diphenylbenzidine (NPB):

A thickness of the HTL may be in a range of about 50 Å to about 2,000 Å, for example, about 100 Å to about 1,500 Å. Maintaining the thickness of the HTL within the above ranges may help provide the HTL, with satisfactory hole transporting capabilities without a substantial increase in a driving voltage.

The H-functional layer (having both hole injection and hole transport capabilities) may include at least one material selected from the above-described materials for the HIL and the HTL. A thickness of the H-functional layer may be in a range of about 50 Å to about 10,000 Å, for example, about 100 Å to about 1,000 Å. Maintaining the thickness of the H-functional layer within the above ranges may help provide the H-functional layer with satisfactory hole injecting and transporting capabilities without a substantial increase in a driving voltage.

In some embodiments, at least one layer of the HIL, the HTL, and the H-functional layer may include at least one of the compounds represented by Formulae 300 and 350 below:

In Formulae 300 and 350, Ar₁₁, Ar₁₂, Ar₂₁, and Ar₂₂ may each independently be a substituted or unsubstituted C₅-C₆₀ arylene group.

In Formula 300, e and f may each independently be an integer of 0 to 5, for example, 0, 1, or 2. In some embodiments, e may be 1 and f may be 0.

In Formulae 300 and 350, R₅₁ to R₅₈, R₆₁ to R₆₉, R₇₁, and R₇₂ may each independently be a hydrogen atom, a deuterium atom, a halogen group, a hydroxyl group, a cyano group, a nitro group, an amino group, an aminido group, a hydrazine, a hydrazone, a carboxyl group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a substituted or unsubstituted C₁-C₆₀ alkyl group, a substituted or unsubstituted C₂-C₆₀ alkenyl group, a substituted or unsubstituted C₂-C₆₀ alkynyl group, a substituted or unsubstituted C₁-C₆₀ alkoxy group, a substituted or unsubstituted C₃-C₆₀ cycloalkyl group, a substituted or unsubstituted C₅-C₆₀ aryl group, a substituted or unsubstituted C₅-C₆₀ aryloxy group, or a substituted or unsubstituted C₅-C₆₀ arylthio group. For example, R₅₁ to R₅₈, R₆₁ to R₆₉, R₇₁, and R₇₂ may each independently be a hydrogen atom; a deuterium atom; a halogen group; a hydroxyl group; a cyano group; a nitro group; an amino group; an amidino group; a hydrazine; a hydrzaone; a carboxyl group or a salt thereof; a sulfonic acid group or a salt thereof; a phosphoric acid group or a salt thereof; a C₁-C₁₀ alkyl group (e.g., a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, and a hexyl group); a C₁-C₁₀ alkoxy group (e.g., a methoxy group, an ethoxy group, a propoxy group, a butoxy group, and a pentoxy group); a C₁-C₁₀ alkyl group and a C₁-C₁₀ alkoxy group, each substituted with at least one substituent selected from a deuterium atom, a halogen group, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine, a hydrzaone, a carboxyl group or a salt thereof, a sulfonic acid group or a salt thereof, and a phosphoric acid group or a salt thereof; a phenyl group; a naphthyl group; an anthryl group; a fluorenyl group; a pyrenyl group; and a phenyl group, a naphthyl group, an anthryl group; a fluorenyl group, and a pyrenyl group, each substituted with at lest one substituent selected from a deuterium atom, a halogen group, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine, a hydrazone, a carboxyl group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C₁-C₁₀ alkyl group, and a C₁-C₁₀ alkoxy group.

In Formula 300, R₅₉ may be a phenyl group; a naphthyl group; an anthryl group; a biphenyl group; a pyridyl group; and a phenyl group, a naphthyl group, an anthryl group, a biphenyl group, and a pyridyl group, each substituted with at least one substituent selected from a deuterium atom, a halogen group, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine, a hydrazone, a carboxyl group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a substituted or unsubstituted C₁-C₂₀ alkyl group, and a substituted or unsubstituted C₁-C₂₀ alkoxy group.

According to another embodiment, the compound of Formula 300 may be represented by Formula 300A below:

In Formula 300A, R₅₁, R₆₁, R₆₂, and R₅₉ may be as defined above.

For example, at least one layer of the HIL, HTL, and the H-functional layer may include at least one of Compounds 301 to 320:

At least one layer of the HIL, HTL, and the H-functional layer may include a charge-generating material in addition to hole-injecting materials, hole-transporting materials, and/or H-functional materials having both hole injection and hole transport capabilities, to improve conductivity of a film.

The charge-generating material may be, for example, a p-dopant. Exemplary p-dopants include quinone derivatives, such as tetracyanoquinodimethane (TCNQ) and 2,3,5,6-tetrafluoro-tetracyano-1,4-benzoquinodimethane(F4-TCNQ); metal oxides, such as a tungsten oxide and a molybdenum oxide; and cyano group-containing compound, such as Compound 200 below:

When the HIL, the HTL, or the H-functional layer includes a charge-generating material, the charge-generating material may be homogeneously dispersed or non-homogeneously distributed throughout the above-described layers.

A buffer layer may be disposed between at least one of the HIL, HTL, and the H-functional layer, and the EML. The buffer layer may compensate for an optical resonance distance of light according to a wavelength of the light emitted from the EML, and may increase efficiency. The buffer layer may include any hole injecting material or hole transporting material. In some other embodiments, the buffer layer may include the same material as one of the materials included in the HIL, the HTL, and the H-functional layer that underlie the buffer layer.

Then, an EML may be formed on the HIL, the H-functional layer, or the buffer layer by vacuum deposition, spin coating, casting, or LB deposition. When the EML is formed by vacuum deposition or spin coating, the deposition and coating conditions may be similar to those for the formation of the HIL, although the conditions for deposition and coating may vary according to the compound that is used to form the EML.

The EML may include a compound represented by Formula 1 or a host and a dopant. In regard to the dopant, the compound represented by Formula 1, a fluorescent dopant, or a phosphorescent dopant may be used.

For example, the host may be Alq₃, 4,4′-N,N′-dicarbazole-biphenyl (CBP), poly(n-vinylcarbazole) (PVK), 9,10-di(naphthylene-2-yl)anthracene (ADN), TCTA, 1,3,5-tris(N-phenylbenzimidazole-2-yl)benzene (TPBI), 3-tert-butyl-9,10-di(naphth-2-yl)anthracene (TBADN), E3, distyrylarylene (DSA), dmCBP (see Formula below), or Compounds 501 to 509 below:

In some embodiments, an anthracene-based compound represented by Formula 400 below may be used as the host:

In Formula 400, Ar₁₁₁ and Ar₁₁₂ may each independently be a substituted or unsubstituted C₅-C₆₀ arylene group; Ar₁₁₃ to Ar₁₁₆ may each independently be a substituted or unsubstituted C₁-C₁₀ alkyl group, or a substituted or unsubstituted C₅-C₆₀ aryl group; and g, h, I, and j may each independently be an integer of 0 to 4.

In some embodiment, in Formula 400, Ar₁₁₁ and Ar₁₁₂ may each independently be a phenylene group, a naphthylene group, aphenanthrenylene group, or a pyrenylene group; or a phenylene group, a naphthylene group, a phenanthrenylene group, a fluorenyl group, or a pyrenylene group, each substituted with at least one substituent selected from a phenyl group, a naphthyl group, and an anthryl group.

In Formula 400, g, h, I and j may be each independently, 0, 1, or 2.

In Formula 400, Ar₁₁₃ to Ar₁₁₆ may each independently be a C₁-C₁₀ alkyl group substituted with at least one of a phenyl group, a naphthyl group, and an anthryl group; a phenyl group; a naphthyl group; an anthryl group; a pyrenyl group; a phenanthrenyl group; a fluorenyl group; a phenyl group, a naphthyl group, an anthryl group, a pyrenyl group, a phenanthrenyl group, and a fluorenyl group, each substituted with at least one substituent selected from a deuterium atom, a halogen group, a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine, a hydrazone, a carboxyl group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a phenyl group, a naphthyl group, an anthryl group, a pyrenyl group, a phenanthrenyl group, and a fluorenyl group; and

In some embodiments, the anthracene-based compounds of Formula 400 above may be any one of the compounds represented by the Formulae below:

In some embodiments, an anthracene-based compound represented by Formula 401 below may be used as the host:

In Formula 401, Ar₁₂₂ to Ar₁₂₅ may be defined as described above in conjunction with Ar₁₁₃ of Formula 400, and thus detailed descriptions thereof will not be provided here.

In Formula 401 above, Ar₁₂₆ and Ar₁₂₇ may each independently be a C₁-C₁₀ alkyl group (e.g., a methyl group, an ethyl group, or a propyl group).

In Formula 401 above, k and l may each independently be an integer from 0 to 4, for example, 0, 1, and 2.

In some embodiments, the anthracene compound of Formula 401 above may be any one of the compounds represented by the Formulae below:

When the OLED is a full color OLED, the EML may be patterned into a red EML, a green EML, and a blue EML.

Meanwhile, at least one layer of the red EML, the green EML, and the blue EML may include one of dopants below (ppy=phenylpyridine).

Examples of the blue dopant include the compound represented by Formula 1 or compounds represented by the Formulae below:

Examples of the red dopant include compounds represented by the Formulae below:

Examples of the green dopant include compounds represented by the Formulae below:

Exemplary dopants used in the EML include a Pd-complex or a Pt-complex represented by the Formulae below:

Alternatively, exemplary dopants used in the EML include an Os-complex represented by the Formulae below:

When the EML includes a host and a dopant, an amount of the dopant may be in a range of, for example, about 0.01 to about 15 parts by weight based on 100 parts by weight of the host.

A thickness of the EML may be in a range of about 100 Å to about 1,000 Å, for example, about 200 Å to about 600 Å. Maintaining the thickness of the EML within the above ranges may help provide the EML with satisfactory light-emitting capabilities without a substantial increase in driving voltage.

Then, an ETL may be formed on the EML by various methods, such as vacuum deposition, spin coating, and casting. When the ETL is formed by vacuum deposition or spin coating, the deposition and coating conditions may be similar to those for the formation of the HIL, although the deposition and coating conditions may vary depending on the compound that is used to form the ETL.

A material that may stably transport electrons that may be injected from an electron injection electrode (i.e., a cathode) may be used as an ETL-forming material.

Examples of ETL-forming materials include a quinoline derivative such as tris(8-quinolinorate)aluminum (Alq₃), TAZ, Balq, beryllium bis(benzoquinolin-10-olate (Bebq₂), ADN, Compound 201, and Compound 202:

A thickness of the ETL may be in a range of about 100 Å to about 1,000 Å, for example, about 150 Å to about 500 Å. Maintaining the thickness of the ETL within the above ranges may help provide the ETL with satisfactory electron transporting capabilities without a substantial increase in driving voltage.

In some embodiments, the ETL may further include a metal-containing material, in addition to an organic compound for the ETL.

The metal-containing material may include a lithium (Li) complex. Exemplary Li complexes include lithium quinolate (LiQ) and Compound 203 below:

Then, and EIL, which facilitates injection of electrons form the cathode, may be formed on the ETL. Any suitable electron-injecting material may be used to form the EIL.

Exemplary EIL-forming materials include Lif, NaCl, CsF, Li₂O, and BaO. Deposition conditions of the EIL may be similar to those for the formation of the HIL although the conditions may vary depending on the compound that is used to form the EIL.

A thickness of the EIL may be in a range of about 1 Å to about 100 Å, for example, about 3 Å to about 90 Å. Maintaining the thickness of the EIL within the above ranges may help provide the EIL with satisfactory electron injection capabilities without a substantial increase in driving voltage.

A second electrode is disposed on the organic layer. When the second electrode is a cathode that may be an electron injection electrode, materials having a low work function, such as a metal, an alloy, and an elctro-conductive compound, and a mixture thereof may be used as the second electrode-forming material. The second electrode may be formed as a thin film type transmission electrode using lithium (Li), magnesium (Mg), aluminum (Al), aluminum-lithium (Al—Li), calcium (Ca), magnesium-indium (Mg—In), magnesium-silver (Mg—Ag). In some other embodiments, to manufacture a top-emission light-emitting diode, the transmission electrode may be formed of indium tin oxide (ITO) or indium zinc oxide (IZO).

The OLED has been described with respect to FIG. 1. Additional embodiments include omission of one or ore of the layers illustrated in FIG. 1 (i.e., EIL, ETL, EML, HTL, and HIL), rearrangement of one or more of the layers illustrated in FIG. 1 and/or additional layers.

When a phosphorescent dopant is used in the EML, a HBL may be formed between the ETL and EML or between the E-functional layer and the EML by vacuum deposition, spin coating, casting, or LB deposition, in order to prevent diffusion of triplet excitons or holes into the ETL. When the HBL is formed by vacuum deposition or spin coating, the conditions for deposition and coating may be similar to those for the formation of the HIL, although the conditions for deposition and coating may vary according to the material that is used to form the HBL. Exemplary hole-blocking materials include oxadiazole derivatives, triazole derivatives, and phenanthroline derivatives. For example, BCP below may be used to form the HBL.

A thickness of the HBL may be in a range of about 20 Å to about 1,000 Å, for example, about 30 Å to about 300 Å. Maintaining the thickness of the HBL within the above ranges may help provide the HBL with satisfactory hole blocking capabilities without a substantial increase in driving voltage.

The OLED according to another embodiment may be provided in various types of flat panel display devices such as passive matrix OLED devices and active matrix OLED devices. For example, when the OLED is provided in an active matrix OLED, the first electrode acting as a pixel electrode on the substrate may be electrically connected to a source electrode or a drain electrode of a thin-film transistor (TFT). In addition, the OLED may be provided in a flat panel display device having double-sided screens.

Alternatively, the organic layer of the OLED according to another embodiment may be formed by vacuum deposition using above-described compounds, or by a wet process that coats the above-described compounds present in a liquid state.

The following Examples and Comparative Examples are provided in order to highlight characteristics of one or more embodiments, but it will be understood that the Examples and Comparative Examples are not to be construed as limiting as limiting the scope of the embodiments, nor are the Comparative Examples to be construed as being outside the scope of the embodiments. Further, it will be understood that the embodiments are not limited to the particular details described in the Examples and Comparative Examples.

EXAMPLES Synthesis Example 1 Synthesis of Compound 2

Synthesis of Intermediate 2-1

4.251 g (10 mmol) of 2,6-dibromo-4phenyl-4H-benzocarboazole, 1.692 g (10 mmol) of diphenzylamine, 0.452 g (0.5 mmol) of tris(dibenzylideneacetone)dipalladium (Pd₂(dba)₃), 0.101 g (0.5 mmol) of PtBu₃, and 0.961 g (10 mmol) of NaO^(t)Bu were dissolved in 150 ml of toluene, and the mixture solution was stirred for 4 hours at a temperature of 90° C. After the mixture solution was cooled down to room temperature, 10 ml of water was added thereto and the mixture solution was extracted three times 50 ml of diethyl ester to obtain an organic layer. Then, the organic layer was dried by magnesium sulfate, and residues obtained by evapaoration of the solvent were separation-purified by silicagel column chromatography to obtain 4.198 g (8.2 mmol, 82%) of Intermediate 2-1.

Synthesis of Intermediate 2-2

3.742 g (10 mmol) of N-(4-bromophenyl)-N-phenyl-2-naphthylamine, 1.848 g (12 mmol) of vinylboronic acid pinacol ester, 0.577 g (0.5 mmol) of Pd(PPh₃)₄, and 0.207 g (15 mmol) of K₂CO₃ were dissolved in 100 ml of mixture solution of THF/H₂O (2/1 volume ratio), the reacting solution was stirred for 12 hours at a temperature of 80° C. After the reacting solution was cooled down to room temperature, 50 ml of water was added thereto and the mixture solution was extracted three times 150 ml of ethyl ester to obtain an organic layer. Then, the organic layer was dried by magnesium sulfate, and residues obtained by evaporation of the solvent were separation-purified by silicagel column chromatography to obtain 2.314 g (7.2 mmol, Yield: 72%) of Intermediate 2-2.

Synthesis of Compound 2

2.567 g (5.0 mmol) of Intermediate 2-1, 1.607 g (5.0 mmol) of Intermediate 2-2, 0.056 g (0.25 mmol) of palladium(II) acetate (Pd(OAc)₂), 0.76 g (0.25 mmol) of P(p-toly)₃, and 1.019 g of (10.0 mmol) Et₃N were dissolved in 50 ml of dimethylacetamide (DMAc), and the mixture solution was stirred for 12 hours at a temperature of 100° C. After the mixture solution was cooled down to room temperature, 30 ml of water was added thereto and the mixture solution was extracted three times 30 ml of diethyl ester to obtain an organic layer. Then, the organic layer was dried by magnesium sulfate, and residues obtained by evaporation of the solvent were separation-purified by silicagel column chromatography to obtain 1.734 g (2.3 mmol Yield: 56%) of Compound 2. The LS/MS and ¹H NMR data of the synthesized compound are shown in Table 1 below.

Synthesis Example 2 Synthesis of Compound 12

Synthesis of Intermediate 12-1

3.9938 g (7.8 mmol, Yield: 78%) of Intermediate 12-1 was synthesized in the same manner as in Synthesis of Intermediate 2-1 in Synthesis Example 1, except that 1,7-dibromo-4-phenyl-4H-benzocarbazole was used instead of 2,6-dibromo-4-phenyl-4H-benzocarbazole.

Synthesis of Compound 12

2.111 g (2.8 mmol, Yield: 56%) of Compound 12 was synthesized in the same manner as in Synthesis of Compound 2 in Synthesis Example 1, except that Intermediate 12-1 was used instead of Intermediate 2-1. The LS/MS and ¹H NMR data are shown in Table 1 below.

Synthesis Example 3 Synthesis of Intermediate 24

Synthesis of Intermediate 24-1

5.116 g (8.0 mmol, Yield: 80%) of Intermediate 24-1 was synthesized in the same manner as in Synthesis of Intermediate 2-2 in Synthesis Example 1, except that 2,6-dibromo-4-(2-naphyhyl)-4H-benzocarbazole instead of N-(4-bromophenyl)-N-phenyl-2-naphthylamine was used and 4-triphenylamine-boronic acid pinacol ester was used instead of vinylboronic pinacol ester.

Synthesis of Intermediate 24-2

865 g (8.7 mmol, Yield: 87%) of Intermediate 24-2 was synthesized in the same manner as in Synthesis of Intermediate 2-1 in Synthesis Example 1, except that vinyl bromide instead of 2,6-dibromo-4-phenyl-4H-benzolcarbazole was used and N-(4-fluorophenyl)-9,9-dimethylfluorenamine was used instead of diphenylamine.

Synthesis of Compound 24

1.776 g (2.0 mmol, Yield: 40%) of Compound 24 was synthesized in the same manner as in Synthesis of Compound 2 in Synthesis Example 1, except that Intermediate 23-1 was used instead of Intermediate 2-1 and Intermediate 2-2 was used instead of Intermediate 2-2. The LS/MS and ¹H NMR data of the synthesized compound are shown in Table 1 below.

Synthesis Example 4 Synthesis of Compound 32

Synthesis of Intermediate 32-1

4.531 g (7.7 mmol, Yield: 77%) of Intermediate 32-1 was synthesized in the same manner as in Synthesis of Intermediate 24-1 in Synthesis Example 3, except that 2,6-dibromo-4-phenyl-4H-benzocarbazole was used instead of 2,6-dibromo-4-(2-naphthyl)-4H-benzocarbazole.

Synthesis of Compound 32

2.337 g (3.1 mmol, Yield: 62%) of Compound 32 was synthesized in the same manner as in Synthesis of Compound 2 in Synthesis Example 1, except that Intermediate 32-1 was used instead of Intermediate 2-1.

Synthesis Example 5 Synthesis of Compound 41

Synthesis of Intermediate 41-1

5.058 g (7.6 mmol, Yield: 76%) of Intermediate 41-1 was synthesized in the same manner as in Synthesis of Intermediate 32-1 in Synthesis Example 4, except that Intermediate 32-1 was used instead of 2,6-dibromo-4-(2-naphthyl)-4H-benzocarbazole and 4-bromophenyl-boronic acid was used instead of 4-triphenylamine-boronic acid pinacol ester.

Synthesis of Intermediate 41-2

2.496 g (9.2 mmol, 92%) of Intermediate 41-2 was synthesized in the same manner as in Synthesis of Intermediate 2-2 in Synthesis Example 1, except that 4-bromo-triphenylamine was used instead of N-(4-bromophenyl)-N-phenyl-2-naphyhylamine.

Synthesis of Compound 41

2.568 g (3.0 mmol, Yield: 60%) of Compound 41 was synthesized in the same manner as in Synthesis of Compound 2 in Synthesis Example 1, except that Intermediate 41-1 was used instead of Intermediate 2-1 and Intermediate 2-2 was used instead of Intermediate 41-2. The LS/MS and ¹H NMR data of the synthesized compound are shown in Table 1 below.

Synthesis Example 6 Synthesis of Compound 50

Synthesis of Intermediate 50-1

4.666 g (7.0 mmol, Yield: 70%) of Intermediate 50-1 was synthesized in the same manner as in Synthesis of Intermediate 41-1 in Synthesis Example 5, except that 5-bromopyridine-2-boronic acid was used instead of 4-bromophenyl-boronic acid.

Synthesis of Intermediate 50-2

1.679 g (8.6 mmol, Yield: 86%) of Intermediate 50-2 was synthesized in the same manner as in Synthesis of Intermediate 2-1 in Synthesis Example 1, except that vinylbromide was used instead of 2,6-dibromo-4-phenyl-4H-benzocarbazole.

Synthesis of Compound 50

2.108 g (2.7 mmol, Yield: 54%) of Compound 50 was synthesized in the same manner as in Synthesis of Compound 2 in Synthesis Example 1, except that Intermediate 50-1 was used instead of Intermediate 2-1 and Intermediate 50-2 was used instead of Intermediate 2-2. The LS/MS and ¹H NMR data of the synthesized compound are shown in Table 1 below.

Synthesis Example 7 Synthesis of Compound 63

Synthesis of Intermediate 63-1

4.775 g (8.1 mmol, Yield: 81%) of Intermediate 63-1 was synthesized in the same manner as in Synthesis of Intermediate 24-1 in Synthesis Example 3, except that 1,7-dibromo-4-(2-naphthyl)-4H-benzocarbazole was used instead of 2,6-dibromo-4-(2-naphthyl)-4H-benzocarbazole.

Synthesis of Compound 63

1.772 g (2.1 mmol, Yield: 42%) of Compound 63 was synthesized in the same manner as in Synthesis of Compound 2 in Synthesis Example 1, except that Intermediate 63-1 was used instead of Intermediate 2-1. The LS/MS and ¹H NMP data of the synthesized compound are shown in Table 1 below.

TABLE 1 LC/MS Compound ¹H NMR (CDCl₃, 300 MHz) found calc. 1 7.94-7.86 (m, 2H), 7.80-7.72 (m, 2H), 7.66-7.42 (m, 627.79 627.27 11H), 7.38-7.15 (m, 11H), 7.05-6.98 (m, 3H), 6.84 (dd, 4H) 2 8.10-8.00 (m, 2H), 7.96-7.66 (m, 12H), 7.62-7.38 (m, 677.95 677.28 6H), 7.30-7.12 (m, 8H), 7.02 (d, 1H), 6.98 (t, 2H), 6.80 (dd, 4H) 3 7.99-7.90 (m, 3H), 7.86-7.68 (m, 8H) 7.65-7.42 (m, 794.42 793.35 11H), 7.40-7.10 (m, 10H), 7.00 (d, 1H), 6.95 (t, 2H), 6.80 (dd, 2H), 1.83 (s, 6H) 6 8.12-8.06 (m, 4H), 7.96-7.66 (m, 12H), 7.62-7.38 (m, 793.95 793.35 6H), 7.30-7.12 (m, 8H), 7.02 (d, 1H), 6.98 (t, 2H), 6.80 (dd, 4H), 7.92 (s, 6H) 8 8.8 (d, 1H), 7.92 (m, 2H), 7.88-7.62 (m, 7H), 7.60- 778.05 777.26 7.15 (m, 19H), 7.10 (s, 1H), 7.05-6.98 (m, 3H), 6.90 (m, 3H) 11 7.94-7.88 (m, 4H), 7.84-7.78 (m, 4H), 7.72-7.54 (m, 704.90 703.30 6H), 7.44-7.34 (m, 8H), 7.15-7.01 (m, 7H), 6.65-6.60 (m, 4H), 6.54-6.48 (m, 4H) 12 8.24 (d, 1H), 7.92-7.84 (m, 3H), 7.82-7.60 (m, 15H), 754.42 753.31 7.48-7.30 (m, 8H), 7.15 (dd, 2H), 7.10-7.01 (m, 4H), 6.64-6.48 (m, 6H) 16 8.18-8.10 (m, 2H), 7.86-7.42 (m, 20H), 7.34-7.20 (m, 803.99 803.33 7H), 7.16 (q, 2H), 7.10-7.02 (m, 4H), 6.64 (dd, 2H), 6.48 (dd, 4H) 22 8.20 (d, 1H), 7.96-7.48 (m, 23H), 7.38-7.28 (m, 4H), 754.56 753.31 7.20-7.16 (m, 2H), 7.10-7.01 (m, 3H), 6.64(dd, 3H), 6.48 (d, 1H) 24 7.99-7.95 (m, 2H), 7.88-7.40 (m, 17H), 7.36-7.18 (m, 888.20 887.37 10H), 7.12-7.06 (m, 3H), 7.00-6.92 (m, 3H), 6.58 (dd, 4H), 6.20 (d, 1H), 1.83 (s, 6H) 25 8.24-8.18 (m, 2H), 8.10-8.02 (m, 2H), 7.84-7.32 (m, 754.28 753.31 27H), 7.14-7.00 (m, 3H), 6.68 (dd, 4H), 6.60 (d, 1H) 29 8.38-8.30 (m, 3H), 8.10 (t, 2H), 7.90-7.36 (m, 23H), 854.10 853.35 7.30-7.16 (m, 7H), 7.10-7.02 (m, 4H), 6.68 (dd, 4H) 32 8.10 (d, 2H), 7.96-7.66 (m, 16H), 7.62-7.38 (m, 6H), 753.99 753.31 7.28-7.12 (m, 7H), 6.88-6.76 (m, 4H), 6.48 (dd, 4H) 36 8.10 (d, 2H), 8.06-7.98 (m, 4H), 7.90-7.70 (m, 9H), 840.02 869.38 7.62-7.18 (m, 18H), 7.13-7.02 (m, 4H), 6.80 (dd, 4H), 1.72 (s, 6H) 37 8.34-8.20 (m, 5H), 7.96-7.56 (m, 14H), 7.46-7.22 (m, 774.18 773.30 12H), 6.88 (dd, 4H), 6.20(d, 1H) 41 8.20 (d, 1H), 7.96-7.64 (m, 16H), 7.42-7.28(m, 8H), 780.16 779.33 7.10-7.00 (m, 8H), 6.64 (dd, 4H), 6.54(dd, 4H) 46 8.24-8.18 (m, 2H), 8.10-8.02 (m, 2H), 7.84-7.64 (m, 804.28 803.33 12H), 7.58-7.18(m, 17) 7.10-7.00 (m, 3H), 6.68 (dd, 2H), 6.60 (d, 1H) 49 8.20 (d, 1H), 7.96-7.64 (m, 14H), 7.58-7.28 (m, 17H), 780.26 779.33 6.92-6.72 (m, 4H), 6.64 (dd, 4H), 6.54(dd, 1H) 50 8.20 (d, 1H), 7.96-7.86 (m, 3H), 7.80-7.28(m, 27H), 781.48 780.33 7.10-6.96 (m, 4H), 6.60 (dd, 4H), 6.54(d, 1H) 57 8.18 (d, 1H), 7.94-7.56 (m, 16H), 7.34-7.14(m, 8H), 780.22 779.33 7.05-6.86 (m, 8H), 6.68-6.50 (m, 8H) 63 8.32 (d, 1H), 7.96-7.56(m, 21H), 7.42-7.10(m, 15H), 830.10 829.35 6.62 (dd, 2H), 6.54(dd, 4H) 65 8.18 (dd, 2H), 7.90-7.52 (m, 18H), 7.40-7.24(m, 8H), 856.40 855.36 7.18 (d, 1H), 7.10-6.96 (m, 8H), 6.62-6.50 (m, 8H)

Other additional compounds were synthesized by using the above-described synthesis pathways using suitable intermediate materials.

Synthesis pathways of other compounds other than the above-described compounds may be also easily recognized by one of skill in the art based on the above-described synthesis pathways and the above-described raw materials.

Example 1

An anode was prepared by cutting an ITO Corning glass substrate (15 Ω/cm² (1200 Å into a size of 50 mm×50 mm×0.7 mm, followed by ultrasonic cleaning for about 5 minutes each time by using isopropyl alcohol and pure water. After that, the ITO glass substrate was subject to UV irradiation for about 30 minutes and exposure to ozone for cleaning, and then, the ITO glass substrate was loaded into a vacuum deposition device.

Next, 2-TNATA was deposited on top of the ITO glass substrate to form an HIL having a thickness of 600 Å. Then, NPB was deposited on the HIL to form an HTL having a thickness of 300 Å.

DNA as a blue fluorescent host and Compound 2 as a blue dopant were co-deposited on the HTL in a weight ratio of 98:2 to form an EML having a thickness of 300 Å.

After that, Alq₃ compound was deposited on the EML to form an ETL having a thickness of 300 Å. Then, Lif as an EIL and AI as a cathode were sequentially deposited on the ETL to a thickness of 10 Å and 3,000 Å, respectively, thereby completing a manufacture of an OLED.

Example 2

An OLED was manufactured in the same manner as in Example 1, except that Compound 12 was used instead of Compound 2 to form an EML.

Example 3

An OLED was manufactured in the same manner as in Example 1, except that Compound 24 was used instead of Compound 2 to form an EML.

Example 4

An OLED was manufactured in the same manner as in Example 1, except that Compound 32 was used instead of Compound 2 to form an EML.

Example 5

An OLED was manufactured in the same manner as in Example 1, except that Compound 41 was used instead of Compound 2 to form an EML.

Example 6

An OLED was manufactured in the same manner as in Example 1, except that Compound 50 was used instead of Compound 2 to form an EML.

Example 7

An OLED was manufactured in the same manner as in Example 1, except that Compound 63 was used instead of Compound 2 to form an EML.

Comparative Example 1

An OLED was manufactured in the same manner as in Example 1, except that DPAVBi was used instead of Compound 2 as a blue fluorescent dopant to form an EML.

As a result of using the compounds of Formula 1 as a dopant of a blue EML, an OLED using the compounds exhibit excellent I-V-L (Current-Voltage-Luminance) characteristics with a decreased driving voltage and an improved efficiency, compared to the blue dopant DPVBi. Lifespan is improved, and the representative characteristics and lifespan results are summarized in Table 2 below.

TABLE 2 Driving Current Half lifespan voltage density Brightness Efficiency Emitting (hr @100 Emission (V) (mA/cm²) (cd/m²) (cd/A) color mA/cm²) Example 1 Compound 2 6.14 50 3,050 6.10 Blue 310 hr Example 2 Compound 12 6.22 50 3,290 6.58 Blue 315 hr Example 3 Compound 24 6.35 50 3,210 6.42 Blue 325 hr Example 4 Compound 32 6.84 50 3,100 6.20 Blue 298 hr Example 5 Compound 41 6.04 50 3,425 6.85 Blue 334 hr Example 6 Compound 50 6.38 50 3,270 6.54 Blue 308 hr Example 7 Compound 63 6.42 50 3,335 6.67 Blue 332 hr Comparative DPAVBi 7.25 50 2,175 4.35 Blue 204 hr Example 1

As described above, according to the one or more of the above embodiments of, an organic light-emitting diode including a heterocyclic compound represented by Formula 1 may have excellent emission capability. For example, the compound is suitable for fluorescent and phosphorescent devices of blue color, especially for a blue fluorescent device. An organic light-emitting diode including the compound may have high efficiency, low voltage, high brightness, and long lifespan.

By way of summation and review, an OLED may have a structure including a substrate, an anode formed on the substrate, and a hole transport layer (HTL), an emission layer (EML), an electron transport layer (ETL), and a cathode that are sequentially stacked on the anode. The HTL, the EML, and the ETL are organic thin films formed using organic compounds.

When a voltage is applied between the anode and the cathode, holes injected from the anode pass via the HTL and migrate toward the EML, and electrons injected from the cathode pass via the ETL and migrate toward the EML. The holes and the electrons are recombined with each other in the EML to generate excitons. Then, the excitons are transitioned from an excited state to a ground state, thereby generating light.

According to an embodiment, provided is a material that may have excellent electrical stability, high charge-transport ability or light-emitting ability, high glass transition temperature, and the ability to prevent crystallization, for example, in comparison with organic monomolecular materials, One or more embodiments include a material that may be suitable for fluorescent and phosphorescent devices of various colors including red, green, blue, and white.

An organic light-emitting diode (OLED) including blue light-emitting compound having a diphenylanthracene structure in the center and an aryl group substituted at a terminal thereof may have low emission efficiency and insufficient brightness. An OLED including a substituted pyrene-based compound may have low blue color purity such that it is hard to implement deep blue, and may have problems in implementation of a full color display with natural colors.

According to an embodiment the heterocyclic compound represented by Formula 1 may have excellent emission capability. For example, the heterocyclic compound represented by Formula 1 may be suitable for fluorescent and phosphorescent devices of blue color, especially for a blue fluorescent device. One or more embodiments include an organic light-emitting diode (OLED) including the heteocyclic compound represented by Formula 1 and having high efficiency, low driving voltage, high brightness, and long lifespan.

Example embodiments have been disclosed herein, and although specific terms are employed, they are used and are to be interpreted in a generic and descriptive sense only and not for purpose of limitation. In some instances, as would be apparent to one of skill in the art as of the filing of the present application, features, characteristics, and/or elements described in connection with a particular embodiment may be used singly or in combination with features, characteristics, and/or elements described in connection with other embodiments unless otherwise specifically indicated. Accordingly, it will be understood by those of skill in the art that various changes in form and details may be made without departing from the spirit and scope of the present invention as set forth in the following claims. 

What is claimed is:
 1. A heterocyclic compound represented by Formula 1:

wherein: R₁ is a substituted or unsubstituted C₁-C₆₀ alkyl group, a substituted or unsubstituted C₃-C₆₀ cycloalkyl group, a substituted or unsubstituted C₆-C₆₀ aryl group, a substituted or unsubstituted C₂-C₆₀ heteroaryl group, or a substituted or unsubstituted C₆-C₆₀ condensed polycyclic group, Ar₁ to Ar₄ are each independently a substituted or unsubstituted C₆-C₆₀ aryl group, a substituted or unsubstituted C₂-C₆₀ heteroaryl group, or a substituted or unsubstituted C₆-C₆₀ condensed polycyclic group, and X, Y, and Z are each independently a single bond, a substituted or unsubstituted C₆-C₆₀ arylene group, a substituted or unsubstituted C₂-C₆₀ heteroarylene group, or a substituted or unsubstituted C₆-C₆₀ condensed polycyclic group.
 2. The heterocyclic compound as claimed in claim 1, wherein R₁ in Formula 1 is represented by one of Formula 2a to 2d:

wherein: Q₁ is —CR₁₁R₁₂—; R₁₁, R₁₂, and Z₁ are each independently a hydrogen atom, a deuterium atom, a substituted or unsubstituted C₁-C₂₀ alkyl group, a substituted or unsubstituted C₆-C₂₀ aryl group, a substituted or unsubstituted C₂-C₂₀ heteroaryl group, a substituted or unsubstituted C₆-C₂₀ condensed polycyclic group, a halogen group, a cyano group, a nitro group, a hydroxyl group, or a carboxyl group, wherein Z₁ is identical to or different from each other when there is a plurality of Z₁s; in Formula 2a, p is an integer of 1 to 5; in Formula 2b, p is an integer of 1 to 7; in Formula 2c, p is an integer of 1 to 4; in Formula 2d, p is an integer of 1 to 7; and * indicates a binding site.
 3. The heterocyclic compound as claimed in claim 1, wherein Ar₁ to Ar₄ in Formula 1 are each independently represented by one of Formulae 3a to 3f:

wherein: Q₁ is —CR₁₁R₁₂—; R₁₁, R₁₂, and Z₁ are each independently a hydrogen atom, a deuterium atom, a substituted or unsubstituted C₁-C₂₀ alkyl group, a substituted or unsubstituted C₆-C₂₀ aryl group, a substituted or unsubstituted C₂-C₂₀ heteroaryl group, a substituted or unsubstituted C₆-C₂₀ condensed polycyclic group, a halogen group, a cyano group, a nitro group, a hydroxyl group, a carboxyl group, or a substituted or unsubstituted C₃-C₂₀ alkylsilyl group, wherein Z₁ is identical to or different from each other when there is a plurality of Z₁s; in Formula 3a, p is an integer of 1 to 5; in Formula 3b, p is an integer of 1 to 7; in Formula 3c, p is an integer of 1 to 4; in Formula 3d, p is an integer of 1 to 7; in Formula 3e, p is an integer of 1 to 3; in Formula 3f, p is an integer of 1 to 9; and * indicates a binding site.
 4. The heterocyclic compound as claimed in claim 1, wherein X, Y, and Z in Formula 1 are each independently a single bond or represented by one of Formulae 4a to 4e:

wherein: Q₁ is —CR₁₁R₁₂—; R₁₁ and R₁₂ are each independently a hydrogen atom, a deuterium atom, a substituted or unsubstituted C₁-C₂₀ alkyl group, a substituted or unsubstituted C₆-C₂₀ aryl group, a substituted or unsubstituted C₂-C₂₀ heteroaryl group, a substituted or unsubstituted C₆-C₂₀ condensed polycyclic group, a halogen group, a cyano group, a nitro group, a hydroxyl group, or a carboxyl group; and * indicates a binding site.
 5. The heterocyclic compound as claimed in claim 1, wherein R₁ in Formula 1 is represented by one of Formulae 5a and 5b:

wherein * indicates a binding site.
 6. The heterocyclic compound as claimed in claim 1, wherein Ar₁ to Ar₄ in Formula 1 are each independently represented by one of Formulae 6a to 6d:

wherein * indicates a binding site.
 7. The heterocyclic compound as claimed in claim 1, wherein X, Y, and Z in Formula 1 are each independently a single bond or represented by one of Formulae 7a and 7b:

wherein * indicates a binding site.
 8. The heterocyclic compound as claimed in claim 1, wherein the compound represented by Formula 1 is any one of compounds 2, 12, 24, 32, 41, 50, and 63:


9. An organic light-emitting diode, comprising: a first electrode; a second electrode facing the first electrode; and an organic layer disposed between the first electrode and the second electrode, the organic layer including the heterocyclic compound as claimed in claim
 1. 10. The organic light-emitting diode as claimed in claim 9, wherein the organic layer is a hole transport layer, a hole injection layer, a functional layer having both hole injection and hole transport capabilities, or an emission layer.
 11. The organic light-emitting diode as claimed in claim 9, wherein the organic layer includes an emission layer, and, optionally, one or more of an electron injection layer, an electron transport layer, a functional layer having both electron injection and electron transport capabilities, a hole injection layer, a hole transport layer, or a functional layer having both hole injection and hole transport capabilities, wherein the emission layer includes an anthracene-based compound, an arylamine-based compound, or a styryl-based compound.
 12. The organic light-emitting diode as claimed in claim 9, wherein the organic layer includes an emission layer, and, optionally, one or more of an electron injection layer, an electron transport layer, a functional layer having both electron injection and electron transport capabilities, a hole injection layer, a hole transport layer, or a functional layer having both hole injection and hole transport capabilities, wherein the emission layer includes at least one of a red emission layer, a green emission layer, a blue emission layer, or a white emission layer that includes a phosphorescent compound.
 13. The organic light-emitting diode as claimed in claim 12, wherein the hole injection layer, the hole transport layer, or the functional layer having both hole injection and hole transport capabilities includes a charge-generating material.
 14. The organic light-emitting diode as claimed in claim 13, wherein the charge-generating material is a p-dopant.
 15. The organic light-emitting diode as claimed in claim 14, wherein the p-dopant is a quinone derivative.
 16. The organic light-emitting diode as claimed in claim 14, wherein the p-dopant is a metal oxide.
 17. The organic light-emitting diode as claimed in claim 14, wherein the p-dopant is a cyano group-containing compound.
 18. The organic light-emitting diode as claimed in claim 9, wherein the organic layer includes an electron transport layer, which includes a metal complex.
 19. The organic light-emitting diode as claimed in claim 9, wherein the organic layer is formed by a wet process.
 20. The organic light-emitting diode as claimed in claim 9, wherein the first electrode of the organic light-emitting diode is electrically connected to a source electrode or a drain electrode in a thin film transistor (TFT). 